Dr. J. E. Gray on the Species of Crocodiles* 267 



The intermaxillary bone in Bombifrons and Palinia is short 

 and truncated behind. In Halcrosia it is rather produced be- 

 hind, the straight sides converging to a point. In all the 

 other genera it is produced behind, with the hinder edge con- 

 verging on the sides and truncated at the ends. 



The palatal bone in all the genera is truncated or rounded in 

 front, except in Mecistops, where it is narrow, short, and acute 

 in front. 



The dorsal scales present considerable variations in different 

 specimens from the same locality; but, allowing for such varia- 

 tions, the genera may be arranged thus : — 



1. The dorsal scales nearly uniformly keeled, in four or six 

 longitudinal series ; the outer series ovate- elongate. Oopholis. 



2. The dorsal scales nearly uniformly keeled, quadrilateral, as 

 broad as long. Crocodilus, Palinia, Molinia, and Mecistops. 



3. The dorsal scales quadrilateral, as broad as long ; the ver- 

 tebral series scarcely keeled, the lateral series irregular and 

 keeled. Halci'osia and Molinia. 



The eyelid of the genus Halcrosia is thickened, with three 

 hard bony plates, as in some of the Alligators, with which it also 

 agrees in the external form of the head and the disposition of the 

 nuchal shield. In all the other genera they are thin and mem- 

 branaceous. 



The Crocodiles {Crocodilidce) may be thus divided : — 



I. The nape with a rhombic disk formed of six plates, which is well separated 

 from the dorsal shields. Normal Crocodiles. 



A. Nuchal scutella none. Dorsal scales in four or six longitudinal series; 

 the outer series ovate-elongate. Toes webbed. Legs fringed. The 

 intermaxillary bone produced, truncated, and converging on the sides. 

 Estuariue or brackish-water Crocodiles. 



1. Oopholis. 



Face oblong ; orbits with an elongated, longitudinal, more or 

 less sinuous ridge in front. Nuchal shields none, or rudimentary. 

 Cervical disk rhombic, of six shields. Dorsal shields uniformiy 

 keeled, in four or six longitudinal series ; the vertebral series 

 with straight internal edges, the outer ovate-elongate. Legs 

 acutely fringed. Toes broadly webbed. Intermaxillary bone 

 produced and truncated behind the suture, sloping backwards 

 and converging, and then transverse or sinuous. 



a. The dorsal scales in six longitudinal series j the vertebral ones elongated 

 like the others. 



1 . Oopholis porosus. 



Crocodilus porosus, Schn. Amph. 159 ; Gray, Cat. Brit. Mus. 58. 

 C. oopholis, Schn. Amph. 



